What's astonishing is that, five years after almost causing the collapse of capitalism as we know it, this cohort is back and doing better than ever.

William D. Cohan, the author of "Money and Power: How Goldman Sachs Came to Rule the World," is a Bloomberg View columnist. He was formerly an investment banker at Lazard Freres & Co., Merrill Lynch and JPMorgan Chase.

By William D. Cohan | Bloomberg News

The most disappointing fact about how little things have changed on Wall Street five years after the collapse of Lehman Brothers Holdings Inc. is not that the Dodd-Frank Act is ineffective. Or that no substantive regulations are in place that might prevent the recurrence of a crisis. Or that no Wall Street executive has been held even remotely accountable for failing to manage his firm effectively. Or even that the Federal Reserve's easing policies have mostly propped up Wall Street banks at the expense of American savers.

No, what is most appalling about the state of play on Wall Street in September 2013 is how much it resembles the state of play on Wall Street in September 2006, when markets were booming, profits were high, and bankers, traders and executives were getting paid small fortunes just to do their jobs. Mostly that meant they were rewarded to take risks with other people's money.

It's all back -- the booming markets, the huge profits (notwithstanding its legal problems, JPMorgan Chase is on track to make $23 billion in net income in 2013) and the excessive pay. The wider economy, meanwhile, is still sluggish and unemployment remains stubbornly high at 7.3 percent, a figure that overlooks those who have given up the job hunt. Interest rates remain artificially low -- to the pain of savers -- thanks to the Fed's relentless buying of $85 billion in Treasury and agency bonds every month.

Then there is the scene in the Hamptons, on the eastern edge of New York's Long Island. According to an excellent yet horrifying Aug. 26 article by Jim Rutenberg in the New York Times, Hamptons builder Joe Farrell is partying like it's 1999.

Farrell, 50, a former commodities trader who left Wall Street in 1995, told Rutenberg: "We're as busy as we've ever been." He noted that he can't keep in stock the speculative homes he builds that cost $3 million to $10 million. "Mostly, though, $3 million to $6 million," he told Rutenberg. "I love that market -- there are probably 10 times as many people in that market than to buy an eight- or nine-million-dollar house, right?"

The builder to the millionaires said he is making as much money as he did in 2006, the peak of the last market cycle, by selling the homes before they are completed, keeping his liquidity high and his debt low.

Farrell isn't building for the hedge-fund crowd, who can afford a much higher price point. Rather, these new homes -- at an average size of 6,500 square feet, with six or seven bedrooms, a pool and a tennis court -- are clearly aimed at the Wall Street banker or trader in his or her late 40s who has been at the game for a decade or more. What's astonishing is that, five years after almost causing the collapse of capitalism as we know it, this cohort is back and doing better than ever.

Some of Rutenberg's additional details of life in the swanky Hamptons make that clear. For instance, Farrell gave Rutenberg a tour of his own $43 million, 17,000-square-foot estate, known as the Sandcastle. It comes complete with "two bowling lanes, a skate ramp, onyx window frames and, just for fun, an A.T.M. regularly restocked with $20,000 in $10 bills." Farrell rents the home for $500,000 for two weeks; last year, Jay-Z and Beyonce were tenants. Farrell also somehow got hedge-fund manager Marc Leder to pay $900,000 for another summer rental.

Rutenberg also reported that local yacht and Porsche sales are climbing again in the Hamptons and that it is no longer unusual for people to buy six-liter bottles of Dom Perignon for $30,000. (Smaller bottles of Dom are going for $8,000 each.) "It was a bit lean for a couple of years in the Hamptons," one local club owner told the Times. "There's this at least perception that we're doing a lot better than perhaps we were, so people are freer to spend money because they're being psychologically conditioned with the highs in the market."

Farrell thinks January's budget deal in Washington, which avoided the so-called fiscal cliff, helped unleash the latest round of animal spirits in the Hamptons. But what sent things into overdrive in his world -- where summer rentals are apparently approaching $1 million a pop -- are the policies of the Federal Reserve. "The stock market's flying through the roof and who's that helping, the middle class? No, I mean that's the reality," he said. "Out here, life goes on."

Sadly, recent data bolster his point. The incomes of the top 1 percent plunged during the recession, but economists Emmanuel Saez and Thomas Piketty show that the wealthy have since recovered almost all their lost ground. The incomes of the other 99 percent, meanwhile, have barely nudged upward. The gains from the bull market in stocks, rising home prices and glowing corporate profits are all flowing to the affluent.

Can the legacy of the 2008 financial crisis really be that the accidental rich have gotten rich again and have returned to their carefree, spendthrift ways? I am all for entrepreneurs getting unlimited financial rewards for figuring out better ways to do the things that people seem to want. But what really sticks in my craw is when the Wall Street bankers and traders who got us into the mess five years ago -- and whom the American people bailed out -- continue to get huge bonuses that come from taking risks with other people's money without so much as a second thought.